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1.
Acta Chir Belg ; 107(4): 449-51, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17966546

RESUMO

Epidermoid splenic cysts are very rare. Symptoms emerge because of enlargement, infection, haemorrhage or rupture. Although splenectomy is indicated for large cysts, minimally invasive and preservation procedures, such as partial splenectomy or total cystectomy with splenorrhaphy, have been increasingly used during the last decade. We report herein the case of a 16-year old female presented with left upper abdominal quadrant pain, fever and abdominal distention treated in our department.


Assuntos
Abscesso/microbiologia , Abscesso/patologia , Cisto Epidérmico/patologia , Esplenopatias/microbiologia , Esplenopatias/patologia , Abscesso/cirurgia , Adolescente , Colágeno/metabolismo , Cisto Epidérmico/metabolismo , Cisto Epidérmico/cirurgia , Feminino , Humanos , Esplenopatias/cirurgia , Esplenomegalia/diagnóstico por imagem , Tomografia Computadorizada por Raios X
2.
Cytobios ; 83(333): 91-103, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8635321

RESUMO

Seven synaptonemal complexes (SC) were present in the pachytene nuclei of Meloidogyne spartinae. The SC was bipartite and consisted of two lateral elements, while lacking a striated central element. This pattern was similar in all Meloidogyne species studied thus far with the exception of M. microtyla. Each SC was attached by only one end to the nuclear envelope while the other end remained unattached and was free in the nucleoplasm. A bouquet formation at pachytene was absent. An average of eight recombination nodules were present on the SC during all stages of pachytene, although the length of SC increased approximately 77%, from an average of 78 to 138 microm from early to mid-late pachytene. In M. spartinae, there was no apparent relationship between SC length and amount of recombination at pachytene. In addition, nuclear volume increased >60% during pachytene while nucleolar volume decreased by approximately 35%. Two nucleolar organizer regions (NOR) were present during mid-pachytene, whereas other stages had only one NOR. This is the first time that two nucleoli have been identified at pachytene in any nematode. They were both the same chromosome yet in reverse order relative to the telomere attached to the nuclear envelope, suggesting that each telomere was competent to interact with the nuclear envelope.


Assuntos
Tylenchoidea/genética , Animais , Feminino , Cariotipagem , Membrana Nuclear/ultraestrutura , Região Organizadora do Nucléolo/ultraestrutura , Oócitos/ultraestrutura , Recombinação Genética , Complexo Sinaptonêmico , Telômero/ultraestrutura
3.
J Nematol ; 25(1): 15-26, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19279736

RESUMO

Hermaphrodites were detected in diploid and polyploid isolates of population 86-Va of Meloidogyne hapla. Young hermaphrodites are indistinguishable from normal females. Initially, hermaphrodite ovaries are filled with oocytes at various stages of development. Hermaphroditism is expressed later when young oocytes in the early pachytene region of the growth zone suddenly advance to diakinesis and proceed with maturation divisions, resulting in spermatid production. Spermatogenesis may be initiated shortly after the fourth molt, or later, after a female has produced some eggs. Spermatogenesis may occur in one or both gonads, and it may be initiated in one gonad before the other. Once initiated, spermatogenesis continues for the entire reproductive life of the hermaphrodite. Several thousand spermatozoa accumulate in the ovotestis. Because they do not pass through the oviduct into the spermatotheca, they do not take part in reproduction (nonfunctional hermaphroditism). Among the progeny of hermaphrodites, ca. 50% are hermaphroditic, and the remainder are apparently normal females which, however, produce about 50% hermaphroditic progeny. Two temperature regimes (20-23 C and 27-30 C) did not influence the percentage of hermaphrodites among the progeny. Hermaphroditism could not be transmitted to nonhermaphroditic isolates following attempted crosses between males of hermaphroditic and females of nonhermaphroditic isolates. Although this result suggests cytoplasmic rather than nuclear inheritance, this conclusion is not definitive.

4.
J Nematol ; 23(2): 249-53, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19283121

RESUMO

Two tetraploid isolates of Meloidogyne hapla, 86P and E289P, with haploid chromosome numbers of 34 and 28, respectively, were studied cytogenetically and biologically in relation to the diploid populations, 86-Va (n = 17) and E289-Taiwan (n = 14), from which they had been originally isolated. Both isolates were quite stable, converting to diploidy at the low rate of about 2.5%. The tetraploid isolate 86P maintained itself in competition with its diploid counterpart in mixed cultures, although an initial frequency of 50% polyploidy was reduced to about 9% at the end of the sixth generation. Both tetraploid isolates could maintain themselves in greenhouse cultures without artificial selection for at least 2 years. Crosses between diploid females and tetraploid males resulted in a few triploid females that produced mostly nonviable eggs, suggesting partial reproductive isolation between the two ploidy forms. Ten generations of propagation of only polyploid females of isolate 86P that were associated with males failed to yield an obligatorily amphimictic isolate that would not convert at all to diploidy. If one accepts a previous assumption that the present day amphimictic root-knot nematodes are tetraploids derived from diploid ancestors, results of the present study are not inconsistent with an evolutionary trend toward an even higher level of ploidy in Meloidogyne, presumably octaploidy.

5.
J Nematol ; 22(1): 10-5, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19287683

RESUMO

Extensive studies during the last 20 years have demonstrated that enzyme phenotypes, especially those of esterases, are species-specific for Meloidogyne and can be used as reliable taxonomic characters for identification of most major and several minor species of this genus. Recent progress in electrophoretic procedures and advanced computer technology have made available automated electrophoretic apparati that can process very thin polyacrylamide slab gels on which the phenotypes of two or more enzymes can be revealed from the protein extract of a single Meloidogyne female. Presently, such apparati facilitate objective species identification. They also are convenient for performing routine field surveys to determine the relative distribution of major Meloidogyne species, conducting population dynamics studies in the field and in microplots, and testing the purity of greenhouse cultures.

6.
J Nematol ; 22(4): 452-6, 1990 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19287745

RESUMO

Controlled crosses of Heterodera glycines were carried out by placing one o r more virgin females of known esterase phenotype on an agar plate and adding, at various time intervals, one or more males of different esterase phenotypes. Progeny (second-stage juveniles) of such crosses were propagated on soybeans, and 30 days later young females were subjected to electrophoretic analysis to determine their esterase phenotype. Esterase phenotypes that represented the heterozygous state of the maternal and paternal genomes confirmed the hybrid nature of the progeny and identified their male parent. When each of 74 females was given the opportunity to mate successively with two males of different esterase phenotypes, 43 mated with a single male and 31 mated with both males. One female mated with three males, i.e., with a male of its own population (sib mating) and the two males provided for the cross. Inseminated females could mate for a second time soon after, or as late as 24 hours after, their first mating. When single males were given the opportunity to mate with many females, about equal numbers of them inseminated zero, one, two, or three females. In greenhouse tests, 12 females were given the opportunity to mate with many males of three different esterase phenotypes. Two females mated with one and possibly more males of the same phenotype, and 10 females mated with males of two different esterase phenotypes. In conclusion, multiple mating appears to be a common behavior of males and females of H. glycines.

7.
Odontostomatol Proodos ; 43(4): 373-9, 1989 Aug.
Artigo em Grego Moderno | MEDLINE | ID: mdl-2518064

RESUMO

The mucous retention cyst of the minor salivary glands represent a specific type of oral mucocele which is lined by epithelium. It is caused probably from partial or complete obstruction of a duct. It affects older patients (over 40 years of age) most commonly women and it is located in different sites than the ordinary mucocele. In this paper we studied the histologic and histochemical features of four cases. The lining epithelium varied from cuboidal to columnar or flattened. Among the cells of the lining epithelium oncocytes were observed.


Assuntos
Mucocele/patologia , Glândulas Salivares Menores/patologia , Glândulas Salivares/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Doenças das Glândulas Salivares/patologia
8.
J Nematol ; 21(2): 260-3, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19287606

RESUMO

Cot curves derived from renaturation kinetics of sheared denatured DNA indicated that the genome of six populations representing the four most common root-knot nematode species (Meloidogyne incognita, M. arenaria, M. javanica, and M. hapla) is composed of 20% repetitive and 80% nonrepetitive sequences of DNA. Cot curves were almost identical, indicating that all populations had a haploid genome of approximately the same size. Calculations from an average Cot curve gave an estimate of 0.51 x 108 nucleotide base pairs for the haploid genome of the four Meloidogyne species. This genome is about 12-13 times larger than the genome of the E. coli strain used as a control.

9.
10.
J Nematol ; 20(1): 1-8, 1988 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19290179

RESUMO

Phenol extraction and cesium trifluoroacetate ultracentrifugation were compared for efficiency in the extraction of DNA from eggs and second-stage juveniles of four species of Meloidogyne. The second method proved to be more satisfactory in that it yielded larger amounts of DNA, shortened the extraction period, and reduced sample handling by eliminating phenol and ether extraction and RNAse treatment. It also made possible the extraction of DNA: from more than one sample at a time. The mean base compositions (% GC) of the total DNA of M. incognita, M. javanica, M. arenaria, and M. hapla, as determined by thermal denaturation tests, were quite similar, as they ranged only between 31 and 33%. Similarly, the thermal stability of the DNA of all four species covered a narrow range from 82.97 to 83.63 C.

11.
J Nematol ; 20(3): 486-92, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19290242

RESUMO

The genetic basis of esterase polymorphism in Heterodera glycines was investigated through controlled matings and analysis of F and F progeny. Three nematode lines, each fixed for a different esterase phenotype, were isolated and purified through repeated directional selection and inbreeding. Each phenotype was characterized by its distinct pair of closely spaced bands of esterase activity. Single-female single-male crosses were conducted according to a modified agar-plate mating technique. F progeny were homogeneous, exhibiting both parental esterase phenotypes (codominant heterozygotes) but no hybrid bands. Approximately 1,500 F progeny segregated in a 1:2:1 ratio for expression of the esterase phenotypes of the female parental line, the heterozygote, and the male parental line. Apparently the three esterase phenotypes correspond to three codominant alleles of a single esterase locus. Reciprocal crosses gave similar results, suggesting no maternal inheritance.

12.
J Nematol ; 19(1): 1-7, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19290099

RESUMO

Four populations of Meloidogyne spartinae from the coast of North and South Carolina were identical cytogenetically. Fourteen rod-shaped chromosomes were present in oogonia and spermatogonia, whereas seven bivalents were observed in oocytes and spermatocytes. There were no distinguishable sex chromosomes. Chromosome behavior was similar to that of other Meloidogyne species. A slight deviation in morphology of prometaphase bivalents was attributed to an increase in frequency of chiasmata that may be associated with the obligatorily amphimictic reproduction of this nematode. The anatomy of the oviduct-spermatotheca region and most cytogenetic features studied suggested that M. spartinae can be regarded as a root-knot nematode. Its position in the genus Meloidogyne or Hypsoperine can be decided by taxonomists. Its small chromosome number (n = 7) compared to the larger number (n = 13-19) of other Meloidogyne species suggests that, cytologically, M. spartinae stands closer to the ancestral form from which the prescent day root-knot nematodes have evolved.

13.
J Nematol ; 19(1): 8-18, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19290100

RESUMO

Thirty populations of Meloidogyne of diverse geographic origin representing 10 nominal species and various reproductive, cytological, and physiological forms known to exist in the genus were examined to determine their enzymatic relationships. The 184 bands resolved in the study of 27 enzymes were considered as independent characters. Pair-wise comparisons of populations were performed in all possible combinations to estimate the enzymatic distances (ED) and coefficients of similarity (S). A phylogenetic tree was constructed. The apomictic species M. arenaria, M. microcephala, M. javanica, and M. incognita shared a common lineage. M. arenaria was highly polytypic, whereas conspecific populations of M. javanica and M. incognita were largely monomorphic. The mitotic and meiotic forms of M. hapla were very similar (S = 0.93), suggesting that the apomictic race B evolved only recently from the meiotic race A. The five remaining meiotic species (M. chitwoodi, M. graminicola, M. graminis, M. microtyla, and M. naasi - each represented by a single population) were not closely related to each other or to the mitotic species.

14.
J Nematol ; 17(1): 1-5, 1985 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19294050

RESUMO

Studies of oogenesis and spermatogenesis revealed that Meloidogyne nataliei is a diploid, amphimictic species with four (n), relatively large chromosomes, and possibly with an XX female symbol-XY male symbol mechanism of sex determination. It differs considerably from all other amphimictic, or meiotically parthenogenetic, species of Meloidogyne which have 13-18 smaller chromosomes and from Meloidogyne (Hypsoperine) spartinae which has seven. Consequently, the taxonomic position of M. nataliei needs to be re-evaluated. The chromosomes of M. nataliei and their behavior during gametogenesis resemble more closely chromosomes of the genus Heterodera than those of the genus Meloidogyne. This resemblance, however, may not imply a closer phyletic relationship of M. nataliei to heteroderid nematodes.

15.
J Nematol ; 17(1): 6-20, 1985 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19294051

RESUMO

Enzyme phenotypes were obtained for 291 populations from 16 species of Meloidogyne originating from 65 countries. Soluble proteins from macerates of individual egg-laying females were separated by electrophoresis in 0.7-mm-thick polyacrylamide gels. Enzymes investigated were nonspecific esterases, malate dehydrogenase, superoxide dismutase, and glutamate-oxaloacetate transaminase. Esterases were polymorphic and most useful in identification of major species. About 94% of the populations of M. hapla, 98% of M. incognita, and 100% of M. javanica could be identified to species on the basis of esterase phenotypes alone. About 84% of the populations of M. arenaria exhibited three distinct phenotypes. Two of them were highly species specific (accuracy of identification 98-100%). The third, and least prevalent, phenotype occurred also in two other species. Another 12 less common Meloidogyne species, of which only one or a few populations of each were studied, exhibited a variety of esterase phenotypes, some of which may prove to be species specific. Superoxide dismutase phenotypes similarly were helpful in the characterization of certain species; however, the same phenotype was often observed in more than one species. The remaining two enzymes, with few exceptions, proved to be less useful for identification of Meloidogyne species. Multienzyme phenotypes represented by two or more enzymes often offered biochemical profiles more valuable for definitive characterization of Meloidogyne species than single enzymes.

17.
Chromosoma ; 87(1): 117-24, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-7160276

RESUMO

The synaptonemal complexes of three amphimictic (meiotic) strains of Meloidogyne are examined in this study. M. microtyla (n = 19) has a tripartite synaptonemal complex (SC) comprised of two lateral elements and one central region with a distinct central element. The central region of the SC in both M. carolinensis (n = 18) and M. megatyla (n = 18) lack a distinct central element. The evolutionary history is different in the strains since M. microtyla has arisen by a mechanism involving an increase in chromosome number (from an ancestral stock of n = 18) while both M. carolinensis and M. megatyla have maintained the number of chromosomes of the ancestral stock. The structure of the SCs of the latter two strains are identical to the structure of the SC of the meiotic parthenogenetic M. hapla. Thus, the pachytene karyotype of M. carolinensis was reconstructed to establish the pairing pattern and identify any changes that may be related to the different morphology of the SC in an amphimictic stock. Although recombination nodules (RN) have been observed in the parthenogenetic M. hapla, none of the three amphimictic strains had any SC associated structures that resembled a RN.


Assuntos
Cromossomos/ultraestrutura , Meiose , Nematoides/genética , Animais , Evolução Biológica , Nucléolo Celular/fisiologia , Genes , Cariotipagem , Partenogênese , RNA Ribossômico/genética , Reprodução
18.
J Nematol ; 14(4): 540-4, 1982 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19295750

RESUMO

The genetic nature of resistance and its epidemiologic effects on two Meloidogyne incognita populations were assessed in the F hybrid tomato cv. Small Fry. The progeny of a Small Fry x Small Fry cross segregated in a 3:1 resistant:susceptible ratio, indicating the presence of a single, completely dominant resistance gene (LMiR) in Small Fry. In a subsequent experiment, infection frequency and the rate of development of primary infection on resistant Small Fry x Small Fry segregates were compared to those on susceptible segregates and the susceptible cultivar Rutgers. Suppression in both infection frequency and rate of development of primary infection was entirely attributable to gene LMiR. A single egg-mass population of M. incognita propagated for 12 generations on Small Fry showed an increased ability over the wild type population to parasitize plants containing the LMiR gene but failed to completely overcome resistance. The relationship of this phenomenon to the genetics of the Lycopersicon esculentum-M. incognita interaction is discussed.

19.
Int Surg ; 66(1): 85-7, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-7251281

RESUMO

Out of 17 mongrel dogs, 3 were subjected on one and two hours of hemorrhagic shock, while the remaining four served as controls. In five of the thirteen dogs, 30 mg/kg of methylprednisolone sodium succinate were administered intravenously one hour after hemorrhage. All animals were sacrificed at the end of the experiment, their lungs were removed and the sodium and water content was measured. The sodium content was found to be markedly increased at the end of two hours of hemorrhagic shock. This increase was prevented significantly by the administration of pharmacological doses of methylprednisolone given at one hour of hemorrhagic shock. No significant change in total lung water was noted, even after two hours of hemorrhagic shock. The results of this study suggest that early intravenous administration of large doses of methylprednisolone may be beneficial to patients in protracted hemorrhagic shock, who are at high risk of developing pulmonary complications.


Assuntos
Pulmão/análise , Metilprednisolona/uso terapêutico , Choque Hemorrágico/tratamento farmacológico , Sódio/análise , Água/análise , Animais , Cães , Pneumopatias/etiologia , Choque Hemorrágico/complicações , Choque Hemorrágico/metabolismo
20.
Chromosoma ; 84(3): 405-12, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-7327051

RESUMO

Pairing of homologous chromosomes results in the formation of 34 synaptonemal complexes (SC) at pachytene, corresponding to the 34 bivalents at metaphase I. No multivalent associations were observed and pairing occurs two-by-two. The modified SC, which lacks a central element, does not affect the pairing process. Only one end of the SC is attached to the nuclear envelope, although either end can attach. Total SC length and the number of recombination nodules in the tetraploid were about 1.5 times greater than in the diploid.


Assuntos
Aneuploidia , Cromossomos/ultraestrutura , Meiose , Nematoides/genética , Animais , Feminino , Cariotipagem , Microscopia Eletrônica , Nematoides/citologia
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